(NaturalNews) According to the American Cancer Society (ACS), breast cancer is the most common cancer in women, affecting over 200,000 women in the U.S. each year and killing more than 40,000. For American men, cancer of the prostate is the type of malignancy that strikes with the greatest frequency.

The ACS says an estimated 192,280 men will be diagnosed with the disease in 2009 and around 27,360 men will die from it. Based on the assumption that finding breast and prostate cancers in the earliest stages will make them easier to cure and slash mortality rates, for over twenty years the U.S. medical establishment has pushed for mass screenings for these common cancers.

So after two decades, all this testing must have resulted in a huge decline in deaths from these diseases, right?

Wrong.

In an opinion piece published in the October 21st issue of the Journal of the American Medical Association (JAMA), experts from the University of California, San Francisco (UCSF) and the University of Texas (UT) Health Science Center explain that overall breast and prostate cancer rates are higher and far more men and women are being treated. However, the incidence of aggressive or late stage cancers has not been significantly reduced at all. Bottom line: the huge and highly hyped effort to screen the adult population for breast and prostate cancers has not brought about the anticipated decrease in deaths.

"Screening does provide some benefit, but the problem is that the benefit is not nearly as much as we hoped and comes at the cost of over diagnosis and over treatment," said one of the paper's authors, Laura Esserman, MD, MBA, in a statement to the media. Dr. Esserman is a professor of surgery and radiology, director of the UCSF Carol Franc Buck Breast Care Center, and co-leader of the breast oncology program at the UCSF Helen Diller Family Comprehensive Cancer Center.

"We need to focus on developing new tools to identify men and women at risk for the most aggressive cancers, to identify at the time of diagnosis those who have indolent or 'idle' tumors that are not life-threatening. If we can identify groups of patients that don't need much treatment, or don't need to be screened, wouldn't that be great?" she stated. "Screening is by no means perfect. We should want to make it better. For both breast and prostate cancer we need to invest in changing our focus from the cancers that won't kill people to the ones that do."

The JAMA article points out that screening costs an enormous amount of money -- more than $20 billion is spent annually in the U.S. to check people for prostate and breast cancer. And the sheer number of people convinced to have these tests has resulted in far more early cancers being detected than in the past. For example, because of regular prostate screening antigen (PSA) testing, now considered "necessary" for most middle-aged men, the number of American men diagnosed with prostate cancer has almost doubled since l980. The number of woman being diagnosed with breast cancer has nearly doubled over that time as well.

So why do the authors of the JAMA article write "the contribution from screening is uncertain"? Because while screening increases the detection of slow growing tumors, the JAMA authors point out, it too often misses the most aggressive cancers which grow so fast that they are not detected early enough to be cured in many cases. And the cancer experts also point out that many patients are undergoing treatment from cancers that actually pose minimal risk. That's right: despite all the fear and scary statistics loudly publicized about these diseases, having breast or prostate cancer doesn't necessarily mean you have a dangerous disease.

"Without the ability to distinguish cancers that pose minimal risk from those posing substantial risk and with highly sensitive screening tests, there is an increased risk that the population will be over-treated," the authors of the JAMA article conclude.

"The basic assumption that screening programs that find and treat early stage disease will then prevent late-stage disease, or prevent cancer from spreading, may not always be correct. If a tumor is aggressive, finding it early may not prevent death," one of the authors, Ian Thompson, MD, said in a statement to the media. Dr. Thompson is professor and chairman of the Department of Urology at the Cancer Therapy and Research Center at the UT Health Science Center at San Antonio and has authored about 400 scientific articles addressing prevention, early detection, and treatment for prostate, kidney, and bladder cancers.

The JAMA authors are not condemning all cancer screening but getting the word out that it is "most successful when pre-malignant lesions can be detected and eliminated" such as during colonoscopies. And they are calling for these specific recommendations for early detection and prevention:

• The development of tests that distinguish between cancers that are lethal and those that are low-risk.

• A reduction in treatment for low-risk disease. "Diagnosing cancers that don't kill the patient has led to treatment that may do more harm than good," they stated.

• Developing tools for doctors and patients to help them make informed decisions about prevention, screening, biopsy and treatment. This includes providing individualized treatments tailored to a person's specific tumor.

• Working to identify those who are at the highest risk for cancer and using proven prevention interventions to keep them from developing a malignancy in the first place.

"Over the years we have worked hard to find new treatments and new ways of finding disease and many of these interventions when appropriately assessed have saved lives," said Otis W. Brawley, MD, chief medical officer of the American Cancer Society, and professor of hematology, oncology and epidemiology at Emory University, in the press statement. "It is very appropriate that we occasionally step back, assess and reflect on what we in medicine are doing. In the case of some screening for some cancers, modern medicine has overpromised. Some of our successes are not as significant as first thought. Cancer is a complicated disease and too often we have tried to simplify it and simplify messages about it, to the point that we do harm to those we want to help."

NaturalNews has previously reported on serious health issues involving mass screenings for breast and prostate cancer, including a study showing that an increase in mammography screenings is associated with an increased incidence of breast cancer (http://www.naturalnews.com/024901.html). In addition, research published recently in the Journal of the National Cancer Institute concluded over a million American men who were told they had prostate cancer following the advent of PSA tests most likely had no real health problem -- until they started down the path of side-effect laden treatments and became labeled as "cancer patients" (http://www.naturalnews.com/027193_cancer_Pro...).